Monkey puffing is when you are smoking an illicit substance (usually meth) with the use of a glass bubble pipe and instead of sucking the smoke normally, you hit it while pushing little puffs of air in and out using your cheeks, resembling the sound a little monkey makes. The purpose of this method is to a. Check the quality of the substance that you're smoking to see if the smoke falls or rises, due to being stomped on b. For some strange reason you get bigger hits c. It annoys the living piss out of the people you're smoking with so MAYBE they'll go away and stop smoking your dope.
I just saw Julie monkeypuff the new shit we got and she fell over dead! There must be fentanyl in it.